add day 12

12/input.txt

@@ -0,0 +1,34 @@
+initial state: ######....##.###.#..#####...#.#.....#..#.#.##......###.#..##..#..##..#.##..#####.#.......#.....##..
+
+...## => #
+###.. => .
+#.#.# => .
+##### => .
+....# => .
+##.## => .
+##.#. => #
+##... => #
+#..#. => #
+#.#.. => .
+#.##. => .
+..... => .
+##..# => .
+#..## => .
+.##.# => #
+..### => #
+..#.# => #
+.#### => #
+.##.. => .
+.#..# => #
+..##. => .
+#.... => .
+#...# => .
+.###. => .
+..#.. => .
+####. => #
+.#.## => .
+###.# => .
+#.### => #
+.#... => #
+.#.#. => .
+...#. => .

12/input_sample.txt

@@ -0,0 +1,17 @@
+initial state: #..#.#..##......###...###
+
+...## => #
+..#.. => #
+.#... => #
+.#.#. => #
+.#.## => #
+.##.. => #
+.#### => #
+#.#.# => #
+#.### => #
+##.#. => #
+##.## => #
+###.. => #
+###.# => #
+####. => #
+

12/solve01.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python
+
+import re
+
+RE_INIT=re.compile(r'^initial state: ([\#\.]+)$')
+RE_RULE=re.compile(r'^([\#|\.]+) => ([\'#\.])$')
+
+rules = dict()
+start = None
+left_index = 0
+
+def read_input():
+    with open('input.txt', 'r') as f:
+        for line in f:
+            yield line.strip()
+
+def run_generation(pots, left_index = 0):
+    result = ""
+    if not pots.startswith('.....'):
+        pots = '....' + pots
+        left_index -= 4
+    if not pots.endswith('....'):
+        pots = pots + '.....'
+
+    for pos in range(2, len(pots) -2):
+        r_key = pots[pos-2:pos+3]
+        if r_key not in rules:
+            rules[r_key] = '.'
+        result = result + rules[r_key]
+    
+    return (result, left_index+2)
+
+
+for line in read_input():
+   m = RE_INIT.match(line)
+   if m:
+       start = m.group(1)
+       continue
+   m = RE_RULE.match(line)
+   if m:
+       rules[m.group(1)] = m.group(2)
+       continue
+   if len(line) == 0:
+       continue
+   raise Execption('unparseable input')
+
+pots = start
+
+for g in range(20):
+    (pots, left_index) = run_generation(pots, left_index)
+    print("(g:{})(s:{}): {}".format(g+1, left_index,pots))
+
+
+print(sum([k+left_index for k,v in enumerate(pots) if v == '#']))

12/solve02.py

@@ -0,0 +1,75 @@
+#!/usr/bin/env python
+
+import re
+
+RE_INIT=re.compile(r'^initial state: ([\#\.]+)$')
+RE_RULE=re.compile(r'^([\#|\.]+) => ([\'#\.])$')
+
+ITER = 50000000000
+
+rules = dict()
+start = None
+
+def read_input():
+    with open('input.txt', 'r') as f:
+        for line in f:
+            yield line.strip()
+
+def run_generation(pots, left_index = 0):
+    result = ""
+    if not pots.startswith('.....'):
+        pots = '....' + pots
+        left_index -= 4
+    if not pots.endswith('.....'):
+        pots = pots + '.....'
+
+    for pos in range(2, len(pots) -2):
+        r_key = pots[pos-2:pos+3]
+        if r_key not in rules:
+            rules[r_key] = '.'
+        result = result + rules[r_key]
+   
+    return (result, left_index+2)
+
+def analyze_sums(sums, last=10):
+    if len(sums) < last:
+        return None
+    diff = sums[-1] - sums[-2]
+    for i in range(1, last-1):
+        x1 = sums[i*-1]
+        x2 = sums[(i+1)*-1]
+        if diff != (x1 -x2):
+            return None
+
+    return diff
+    
+for line in read_input():
+   m = RE_INIT.match(line)
+   if m:
+       start = m.group(1)
+       continue
+   m = RE_RULE.match(line)
+   if m:
+       rules[m.group(1)] = m.group(2)
+       continue
+   if len(line) == 0:
+       continue
+   raise Execption('unparseable input')
+
+pots = start
+left_index = 0
+g = 0
+sums = []
+sums.append((sum([k+left_index for k,v in enumerate(pots) if v == '#'])))
+while g < ITER:
+    g += 1
+    (pots1, left_index1) = run_generation(pots, left_index)
+    if pots1 == pots:
+        break
+    (pots, left_index) = (pots1, left_index1)
+    print("(g:{})(s:{}): {}".format(g+1, left_index,pots))
+    sums.append((sum([k+left_index for k,v in enumerate(pots) if v == '#'])))
+    diff = analyze_sums(sums)
+    if diff:
+        print(sums[-1]+(diff * (ITER-g)))
+        break